1. Field of the Invention
The present invention relates to a color image forming apparatus configured to form a color image based on image signals, and specifically, relates to a setting technique of an image forming condition thereof.
2. Description of the Related Art
Previously, in e.g. Japanese Patent Application Laid-Open No. 2003-107830, there has been proposed a technique for employing a sensor (color sensor) which detects the color information of a color image after fixing so that a proportion between cyan, magenta, and yellow can be obtained such that process gray becomes an achromatic color or generally achromatic color, thereby achieving gray balance (hereafter, gray axis correction control).
Also, with Japanese Patent Application Laid-Open No. 2005-125714, there has been proposed a technique for executing the above-mentioned gray axis correction control for each type of recording material regarding surface property, saving the execution results thereof, and thereafter, employing the saved execution results at the time of print execution of the corresponding type of recording material. Further, according to Japanese Patent Application Laid-Open No. 2005-125714, there has also been proposed a technique for improving usability such that the execution results of the above-mentioned gray axis correction control are saved regarding the type of recording material which a user desires in accordance with the user's instructions. Note that, in general, the type of recording material also corresponds to the type of print mode, so let us say that the difference between the types of media can be interpreted as the difference between types of print modes.
Also, Japanese Patent Application Laid-Open No. 2005-167550 has proposed a color sensing technique wherein a patch is formed on a recording material serving as a basic type, an image forming condition is set regarding the type of recording material employed for a subsequent job based on the detection result of the patch. Note that this color sensing technique differs from the above-mentioned gray axis correction control. Further, Japanese Patent Application Laid-Open No. 2005-167550 has proposed a technique for forming a patch on all types of recording materials in the image forming apparatus when there is no job reservation, and setting an image forming condition regarding all types of recording material based on the detection results of these patches.
However, with Japanese Patent Application Laid-Open No. 2005-125714, the chromaticity or glossiness is detected regarding a certain type of recording material, and the gray axis correction control is executed, but in the following, the actual value is not updated until a gray axis correction control execution instruction regarding the type of recording material thereof is received. That is to say, usage of consumables, and change in control bias since the gray axis correction control has been performed regarding the same recording material in the past are not taken into consideration. In other words, there has been a case where it is difficult to follow change in image forming conditions (e.g., density/gradation property) due to fluctuation such as toner charge amount and particle sizes due to change in the usage of consumables, difference of transfer selection bias at the time of performing control, or the like. As a result thereof, in order to handle each recording material having multiple types of surface property (corresponding to each print mode), there is room for improvement in printing image quality.
Also, with Japanese Patent Application Laid-Open No. 2005-167550, each time a job of the user's desired media type is input, a patch is formed on a recording material having a basic type, and color sensing is performed. This case includes a problem wherein productivity deteriorates when attempting to obtain excellent image quality overall in order to handle each recording material having multiple types of surface property.
On the other hand, with Japanese Patent Application Laid-Open No. 2005-167550, color sensing is performed for all recording materials at the time of a printer standby (non-printing) state, but this causes a problem wherein significant downtime may occur as to a print execution instruction given by the user at an arbitrary time, in some cases. Also, at this time, there is also a problem wherein a great number of consumables including recording materials are consumed.
To this end, there has been demand for improved printing image quality overall in multiple types of print modes while reducing both downtime and consumption of consumables.